Circular crossflow cooling tower

ABSTRACT

1,074,840. Cooling towers. FLUOR CORPORATION Ltd. Nov. 25, 1964 [Aug. 28, 1964], No. 48005/64. Heading F4K. A cross-flow cooling tower 10 comprises an annular ring of packing 14 surrounding an interior region 13 above which are spaced, about a vertical axis through the tower, a series of fans 16 which provide communication between the interior region and an air exhaust stack 18, the fans drawing cooling air horizontally through the packing and out vertically through the stack via Venturi-shaped fan rings 53. Water distributing means comprise a decking 33 supported on beams 34, the decking having outlet nozzles 36 spaced above the packing ring. Water is supplied to the decking from an annular flume 37 through control gates 39 in the flume wall 40. A cylindrical baffle 15 situated about the vertical axis inside region 13 turns the air flow upwards towards fans 16. Aligned radial partitions 38 and 44 are mounted in vertical planes above the decking 33 and within region 13 respectively, forming decking portions 33a and convergent subregions 13a which direct the incoming air to each fan. Water from the packing rings drop into an annular basin 20 and is collected from a trough 21. The region 13 is covered by a deck 45 which supports the fan driving means 52 and has access provided to it by a tunnel 48 and a staircase 49 inside the baffle 15.

March 29, 1966 R, R QSENGA ET AL 3,243,166

CIRCULAR CROSSFLOW COOLING TOWER Filed Aug. 28, 1964 2 Sheets-Sheet 1 .GIIO

INVENTORS. R. K7S5A/Gn HLA-@E0 L ITL/.L52

March 29, 1966 Filed Aug. 28. 1964 R. R. osENGA ETAL 3,243,166

CIRCULAR CROSSFLOW COOLING TOWER 2 Sheets-Sheet 2 INVENTORS. Rpm/fono R. 05E/v60 ALF-p50 L. UME@ www rrapA/rs.

United States Patent 3,243,166 CIRCULAR CROSSFLOW COOLING TOWER Raymond R. Osenga, Santa Rosa, and Alfred L. Fuller, Fullerton, Calif., assignors to The Fluor Corporation, Ltd., Los Angeles, Calif., a corporation of California Filed Aug. 2S, 1964, Ser. No. 392,844 7 Claims. (Cl. 261-23) This invention relates generally to water cooling towers, and more particularly concerns so-called crossllow cooling towers wherein air passes crosswise of the path of dropping Water and in cooling yrelation therewith.

At the present time cooling towers generally lack certain unusual advantages and features which it is a major object vof the present invention to provide. Among these unusual advantages are the concentration of multiple fans in such a way as to greatly reduce the tower structure size and ground space required for a given water' cooling capacity, a provision for accelerating the iiow of air moving inwardly toward the fans in such manner as to reduce pressure drops, the maintenance of heat load availability despite shutdown of some tower fans, and the ready accessibility of the tower components including fan drives and water distributor means despite their incorporation in a very. large size tower.

These and other uncommon advantages may be considered to result from a novel crossow type cooling tower having a vertical central axis, and including a cham-ber having aninterior region located about the vertical axis, packing extending about the interior region for receiving water dropping downwardly to be contacted `by cooling air passing across the packing 'generally inwardly toward the interior region, an air exhaust stack projecting above the top level of the chamber for receiving airfrom the interior region, and a series of fans spaced about the control axisin open vertical communication with the interior region and stack for displacing air to flow from the interior region upwardly in the stack so that the air .velocity increases gradually as the air passes inwardly across the packing and into the interior region. Typically, the packing extends annularly continuously about the open interior region and concentrically with respect to a cylindrical air bathe projecting vertically in wardly of the open interior region, the result being that the inward air ow accelerates in moving toward the fan. Also, the baiile helps to effect upward turning of the air ow in the interior region and toward the undersides of the fans. A deck typically supports the fans outwardly of a vertical projection of the baie and inwardly of a vertical projection of the stack. Further, upright interior partitions are circularly spaced in the interior region and extend inwardly toward the balile in convergent relation to reduce pressure drops so as to promote operating etilciency.

It is another object of the invention to provide water distributing means extending annularly continuously about the axis of the above described tower and outwardly of a vertical projection of the enlarged diameter stack to supply dropping water for reception by the annular ring of packing. Further objects include the locating of the fans to extend in a horizontal plane suciently above the level of fan supporting decking, and also suficiently outwardly of a vertical projection of the central baille, that air owing into the open interior region of the tower is turned to flow substantially vertically at the deck openings; the inclusion of individual venturi-shaped fan rings within the large outer stack; the forming of the stack as an elevated concrete cylinder supported -by colu-mns located inwardly of the packing, and the clustering of fan drivers inwardly of the fans and on decking to which access may he had through the cylindrical 'bale and via a tunnel extending inwardly to the base of the baie.

HCS

These and other objects and advantages of the invention, as well as the detail-s of an illustrative embodiment, will be more fully understood from the following detailed description of the drawings, in which:

FIG. l is an exterior elevation showing of one form of tower embodying the invention;

FIG. 2 is a plan view of the FIG. l tower;

FIG. 3 is a vertical sectional elevation taken on line 3-3 of FIG. l;

FIG. 4 is an enlarged fragmentary elevational showing of the water distribution system; and

FG. 5 is an enlarged fragmentary elevational showing of the detailed interior construction of the tower.

Referring in detail to the drawings, the cooling tower 10 is of crossow type having a central vertical axis 11, and it includes a chamber 12 having an interior region 13 located about the axis 11. be understood as located inwardly of an annular ring 14 of packing, and outwardly of an upright air halide 15,`

the ring of packing 14 and air baffle both extending concentrically about the axis 11. In this connection, it will Ibe understood that the ring of packing is located to receive water dropping downwardly to be contacted by cooling air passing across the packing generally inwardly toward the, interior region 13, the bale 15 func-- tioning to promote -an upward turn-ing of the air ow within the interior region. Additionally, a series of fans 16 is spaced about the axis 11 in vertical communication with the interior region 13 of the tower as .well as with the interior 17 of a stack 18 for displacing air to flow from the interior region 13 upwardly in the stack, with the result that the air velocity increases during its travel inwardly across the packing and Iinto the interior region 13 in such manner as to avoid sharp accelerations and corresponding pressure drops during its coursing to the fans 16.

More specifically, the tower 12 typically comprises a relatively large concrete structure having a lloor 19 sloping downwardly away from axis 11 toward an annular basin 20 that includes `an annular trough 21, there being appropriate ring footings 22, 23, 24, 25 and 26 for the tower structure. The concrete 'stack 18 which encompasses the fans is carried by columns 27, best seen in FIG. 5, to be spaced apart about the axis 11 in order to pass the cooling air inwardly into the interior region 13 Abelow the fans 16. p

T'he ring 14 of packing is carried on an annular concrete hase y28 supported at 29 directly above the basin in order that water dropping 4through the packing may be collected in the `basin and ultimately in the trough 21 for further use. The packing itself is of suitable cro-ssow type, vertically spaced decks or slats 30 lbeing illustrated in FIGS. 3 and 4 as typical only. In this regard,

it 'will be noted that near optimum utilization of space available lfor the packing is made =by reason of it-s substantially continuous annular extent about the axis 11, thereby to obtain greater cooling capaci-ty for -a given size installation. At the same time, in accordance with the invention, provision is made to avoid abrupt changes in air flow and to yforce gradual inward lacceleration o-f the 'air Iow through the inner contines of 4the packing and into the interior region 13, for the purpose of avoiding sharp pressure drops.

A suitable ring or rings of drift eliminators 31 is located at the inner side of the packing ring 14 and aibove the basin 20 to promote removal of such carry over or drift las does exist in the air stream le'aving the packing and flowing toward the interior region 13. The drift eliminators may include horizontally extending bales 32 angled to receive irnpingement of `the air -streams for separating -out the moisture carried thereby. Finally, the ring Region 13 may further 14 of packing is tapered inwardly yin a downward direction in order that maximum utilization of packing surface may Ibe achieved, in keeping Awith `the tendency for dropping water particles to be displaced linwardly by t le inwardly directed air streams.

Another aspect of the invention has to do with the provision of lwater distributing means extending annularly substantially continually about the axis 11, and also above the packing ring 14 outwardly of `a vertical projection of the enlarged stack d8, for supplying dropping water to the packing. Typically, the =watcr distributing means incl-udes annular decking 33 supported by radial beams 34 carried by circularly spaced tower columns 35. The decking carries water distributing nozzles or outlets 36 spaced above the packing ring 14, and to which water is supplied from an annular fiume 37 extending about the stack fvertical projection. In this re-gard, the annular extent of the decking 33 is ytypically subdivided into sections by the radially extending curbs 38, best seen in FIG. 2, so that each section 33a of decking between successive curbs 38 corresponds to one rfan 16. For example, the air flow through a packing section directly beneath the decking section 33a is ultimately exhausted upwardly through the fans 16 corresponding to that decking section.

In accordance with `a further aspect of the invention, during shutdown of a particular -fan 16, such as for repairs, the water supply `to the packing through which the air is drawn by `that fan can be shut iolf. T-he particular way in which this may be done, as shown in the drawings, is made possible by provision of individual control gates generally indicated at 39 yat the flume Wall 40, there being one such gate for each .section of decking between pairs of curbs 38. Typically, the control gate may include a gate member 41 movable vertically by a handwheel control actuator 42 lto control an outlet in the flume wall 40 for passing water from within the ilume to the decking nozzles, FIG. 4 best illustrating lthis construction. An annular over dlow curb is provided at 43 voutwardly of the bulk of the nozzles 36 to limit the depth of the water spread on the decking 33 and above the nozzles.

yReference .to FIGS. 2 and 3 will show the provision of radially extending vertical partitions 44 inwardly of fthe packing ring 14 and outwardly lof the cylindrical baille 15, the partitions typically reaching from the flooring 19 upwardly to ya deck 45 overlying the interior region `13 of the tower. Accordingly, the vpartitions `form what may be characterized `as sub-regions 13a which correspond to the decking portions 33a inasmuch as the partitions 44 are seen in FIG. 2 -to lie in vertical radial planes dened by the curbs 38. The partitions 44 function by reason of their inwardly convergence to contribute toward acceleration of the lair llow inwardly 'within the sub-regions 13a as the air dow courses ltoward the fans 16, thereby avoiding sharp accelerations and corresponding pressure drops. As indicated in FIG. 3, Ithe partitions may be constructed of slats iextending horizontally and radially. Furthermore, the cylindrical baille promotes upward turning of the kai-r ilow as indicated by the arrow 46 in EFIG. 3 within each sub-region 13a. The 'fans extend in `a horizontal plane spaced suiliciently above the level of the annular decking 33, and the vfans are also spaced Sulliciently outwardly of a vertical projection of the baille '15, that air ilowing into `the sub-regions is turned to llow substantially vertically through the circularly spaced openings 47 in the deck 45, although some swirling motion is imparted to the ilow as it approaches the fans. These air directing |principles afforded 'by the novel construction iof the tower promote high etllciency in terms of low pressure drops resulting from acceleration of the ow and also in terms of high cooling capacity.

It will be noted from FIGS. 1 and 3 that an access tunnel is provided at 48 to extend inwardly of the chamber -for communicating between the exterior Of the tower and the interior of the cylindrical air baille 15. Within the latter, means is provided to gain vertical access to the deck 45, a suitable stairway 49 being -typical of such means. Furthermore, the tan driving means is carried 'by the deck inwardly of the |fans themselves in order that access may be had thereto at a generally central location corresponding to the location of vertical access to the deck 45. The latter contains an opening 50 through which equipment may be hoisted or lowered by a mechanism such :as is indicated at 5'1, the opening 50 overlying the interior of the `cylindrical baille 15. The fan driving means may take the form of motors 52 grouped inwardly of a plurality of venturi-shaped fan rings 53 located Iwithin the stack 18, each ring having Ya vertical axis 54 and extending yabout one yfan to promote upward air llow therethrough in response to Afan rotation. The fan rrnotors 52 typically drive the fans via shafting 55 and vthe right angle drive 56 located at the tan axis 54. A further advan Itageous result of the tower construction involving the use of multiple `fans in the arrangement illustrated is found in that one -or more fans maybe shutdown to partially shutdown the tower while the heat load or cooling capacity is kept `available through the distribution of wateii to be cooled to operating sections of ythe tower. In addition, the stack 118 in combination with the 4fans and venturi rings 53 creates an up draft within rthe stack which tends -to affect equally the pressure conditions at the ventu-ri ring outlets. As a result, one fan is shutdown, air is still drawn vertically through the venturi ring by the up draft conditions in the stack 18 so `that that section of the packing corresponding =to the shutdown tan may still `be operated by supply of water thereto to be `cooled :by the air induced to ow crosswise through the packing and upwardly through the fan ring into the stack.

We claim:

1. yIn a 4crossilow .type cooling tower having a central `vertical axis, means forming a chamber having an interior region located about said axis, upright interior partitions circularly spaced apart in said region and extending inwardly toward said axis, water supply means, packing extending generally annularly and continuously 'about said interior region `for receiving water dropping downwardly from said Water supply means to be contacted by cooling -air passing across said packing generally inwardly toward said interior region, an air exhaust stack extending generally circularly about said yaxis and projecting above the top level of said chamber for receiving air from said interior region, a series of fans having generally vertical axes of rotation spaced circularly `about said axis to locate the fans in open vertical communication with said interior region and stack for displacing air to llow `from said interior region upwardly in said stack so -that the air velocity increases as the lair passes inwardly across said packing and into said interior region, a vertically projecting generally cylindrical air baille extending about said axis inwardly of lsaid interior region `to help eilect an upward turning of the lair Iflow in said interior region and toward the yundersides rof `the fans, land a deck supporting the fans outwardly of a vertical projection of said baille, and inwardly of a vertical projection of said stack, the deck having openings to pass 'air displaced by the fans but otherwise substantially covering said interior region, each opening overlying a sub-region formed between a pair of said interior partitions.

2. T'he combination of claim `1 including an access tunnel extending inwardly of said chamber to communicate Iwith the interior of said cylindrical air baille, means within said baftle providing vertical access to said deck, and atan driving means carried by said deck inwardly of Ithe fans themselves.

3. 'IIhe combination of claim 1 in fwhich the stack com prises fan elevated concrete cylinder, 'and including columns supporting the stack and located inwardly 0f said'l packing.

4. The combination of claim 1 including a plurality of Venturi-shaped fan rings within the stack, each ring hay. ing a vertical axis and extending yabout one fan.`

5. The combination as defined in claim 1 including water distributing means extending lannularly substantially continuously about said axis and extending above the packing outwardly of a vertical projection of the stack to supply dropping IWater for reception by the packing.

6. The combination .of claim 5 in which said water distributing means includes annular decking carrying water distributing nozzles and a diurne extending about said stack vertical projection to sulpply water yto said nozzles.

7. The combination of claim 6 in which the fans extend in la horizontal plane spaced -suiciently above the level of said annular decking `and the 'fans are spaced sufficiently outwardly of -a vertical projection of said baille that air diowing into said sub-regions is turned to flow substantially vertically at ysaid deck openings.

References Cited by the Examiner UNITED STATES PATENTS FOREIGN PATENTS 3 1925 Germany.

12/ 1932 Germany.

5/ 1925 Grealt Britain. 7/ 1960 Great Britain.

15 HARRY B. THORNTON, Primary Examiner.

T. R. MILES, Assistant Examiner. 

1. IN A CROSSFLOW TYPE COOLING TOWER HAVING A CENTRAL VERTICAL AXIS, MEANS FORMING A CHAMBER HAVING AN INTERIOR REGION LOCATED ABOUT SAID AXIS, UPRIGHT INTERIOR PARTITIONS CIRCULARLY SPACED APART IN SAID REGION AND EXTENDING INWARDLY TOWARD SAID AXIS, WATER SUPPLY MEANS, PACKING EXTENDING GENERALLY ANNULARLY AND CONTINUOUSLY ABOUT SAID INTERIOR REGION FOR RECEIVING WATER DROPPING DOWNWARDLY FROM SAID WATER SUPPLY MEANS TO BE CONTACTED BY COOLING AIR PASSING ACROSS SAID PACKING GENERALLY INWARDLY TOWARD SAID INTERIOR REGION, AN AIR EXHAUST STACK EXTENDING GENERALLY CIRCULARLY ABOUT SAID AXIS AND PROJECTING ABOVE THE TOP LEVEL OF SAID CHAMBER FOR RECEIVING AIR FROM SAID INTERIOR REGION, A SERIES OF FANS HAVING GENERALLY VERTICAL AXES OF ROTATION SPACED CIRCULARLY ABOUT SAID AXIS TO LOCATE THE FANS IN OPEN VERTICAL COMMUNICATION WITH SAID INTERIOR REGION AND STACK FOR DISPLACING AIR TO FLOW FROM SAID INTERIOR REGION UPWARDLY IN SAID STACK SO THAT THE AIR VELOCITY INCREASES AS THE AIR PASSES INWARDLY ACROSS SAID PACKING AND INTO SAID INTERIOR REGION, A VERTICALLY PROJECTING GENERALLY CYLINDRICAL AIR BAFFLE EXTENDING ABOUT SAID AXIS INWARDLY OF SAID INTERIOR REGIN TO HELP EFFECT AN UPWARD TURNING OF THE AIR FLOW IN SAID INTERIOR REGION AND TOWARD THE UNDERSIDES OF THE FANS, AND A DECK SUPPORTING THE FANS OUTWARDLY OF A VERTICAL PROJECTION OF SAID BAFFLE, AND INWARDLY OF A VERTICAL PROJECTION OF SAID STACK, THE DECK HAVING OPENINGS TO PASS AIR DISPLACED BY THE FANS BUT OTHERWISE SUBSTANTIALLY COVERING SAID INTERIOR REGION, EACH OPENING OVERLYING A SUB-REGION FORMED BETWEEN A PAIR OF INTERIOR PARTITIONS. 